Icemakers in the freezer section of residential refrigerator freezers are well known and produced and installed in large volume. Typically such icemakers work by:                filling molds with the proper amount of water to make ice bodies of the desired size, without overfilling and spilling excess water,        determining when the water has become solid ice,        performing an action to harvest the ice bodies from the mold and move them to a storage container,        repeating the cycle.To successfully perform the above steps, it is also common that the icemaker:        1. briefly heat the molds to loosen the ice bodies and        2. sense when the storage container is full, to delay moving ice bodies to the storage container until there is room again.        
There are three basic icemaker designs currently on the market. The first design consists of a steel or plastic base, to which a motor, two switches, a gear, a cam and an adjusting lever are attached. A third switch and another lever are attached to the icemaker housing along with the thermostat, heater, wire harness and bail arm (like bail arm 24 that will be in the detailed description of this application). The motor, switches, thermostat, heater and wire harness are all connected with lead wires, making final assembly very labor intensive and prone to wiring errors. Also, the water fill level is controlled by time, which is adjusted by moving one of the switches attached to a lever, which varies the distance between the switch actuator and the cam ramp surface. U.S. Pat. No. 5,823,001 is an example of a patent that refines this first design of an icemaker.
The second design consists of a self-contained control module and the icemaker housing. The control module is made up of a plastic base, to which a number of copper stampings are assembled, then a cam, gear, two levers, adjusting screw and motor are attached. The gear also has a number of copper stampings assembled to it. The switching is accomplished by formed features of the copper stampings in the base contacting the copper stampings in the gear, completing the circuit. Formed features of the copper stampings in the base make the connections to the heater, thermostat and wiring harness when the control module is attached to the icemaker housing. U.S. Pat. Nos. 4,649,717 and 7,146,820 are examples of patents that refine this second design of an icemaker.
The third design consists of an electronic control circuit that replaces the snap switches in the previous two designs with magnetic proximity switches and a liquid level sensor, then the motor, gear and bail arm levers are assembled into the icemaker housing and all electrical connections are made with lead wires. U.S. Pat. No. 6,637,217 is an example of a patent that refines this third design of an icemaker.
Engineers and business people who mass-produce products tend to modularize them into smaller portions. An example of this is the automotive industry, where many subassemblies of a car, for example the engine, chassis, and transmission are designed and built separately. Later these modules are efficiently assembled.
With regards to icemakers, modularization by some manufacturers has changed the terminology used. Formerly, the term “icemaker” referred to the entire device, including a control. U.S. Pat. No. 5,261,248 to Willis et al. is an example of this terminology. In that patent, item 26 is the icemaker and 38 is a control that is a part of the icemaker 26. Currently, with modularization, a device for making ice has a portion referred to as an icemaker control module (ICM) that can be pre-assembled, and attached to an “icemaker” portion. An example of modularized terminology is in U.S. Pat. No. 7,146,820. Many improvements to either the icemaker control module portion, or the icemaker portion, may be done independently of the other.
The design of the icemaker portion has remained fairly constant. It is made of only a few parts so assembly labor is less of an issue. Most of the parts remain stationary and are not subject to wear. The icemaker portion is not responsible for the details of controlling the cycle, so there is less need to improve the design to seek precision and adjustability.
On the other hand, the ICM has many moving parts that must be assembled, leading to high labor costs. The first and third designs mentioned above each have about 40 components, and the second design has about 21 components.
The ICM must operate precisely and reliably. Service technicians may prefer that the icemaker be adjustable should the need arise. Naturally, manufacturers desire to make the pieces, and the assembled ICM, at a reduced cost. Among ways to do this are to reduce the number of parts and improve the manner in which they assemble. Designs and components that can be assembled by automated equipment, with few connections, and little human involvement, are desirable. They further desire that the ICM be able to be assembled to the icemaker portion in equally easy fashion.